Fastener stud



G. M. RAPATA FASTENER STUD May 16, 1967 Original Filed May 5, 1961United States Patent ()fiice 3,3l9,5l Patented May 16, 1967 3,319,510FASTENER STUD George M. Ra ata, Park Ridge, 11L, assignor to IilinoisTool Works Inc., Chicago, Ill., a corporation of Delaware Originalapplication May 5, 1961, Ser. No. 108,110, new

Patent No. 3,162,085, dated Dec. 22, 1964. Eivided and this applicationSept. 8, 1964, Ser. No. 394,748

7 Claims. (Ci. 85-72) V This application is a division of my copendingapplication, Ser. No. 108,110, filed May 5, 1961, now issued as PatentNo. 3,162,085.

The present invention relates to a novel fastening device or anchormember, and more specifically, to novel fastening devices or anchormembers suitable for application to an aperture work structure from oneside thereof.

An important object of the present invention is to provide a novelanchor member or fastening device of resilient or deformable materialwhich may be easily and securely applied to an apertured work structurefrom one side thereof and which may be economically produced.

A further object of the present invention is to provide a novel anchormember or fastening device of the above described type having a portionwhich may be readily inserted into an aperture work structure and whichis adapted to be expanded for sealing the work structure aperture.

A more specific object of the present invention is to provide a novelanchor member or fastening device of resilient or deformable materialwhich is constructed so that a portion thereof may be readily insertedinto a work structure aperture without undue forcing and subsequentlyexpanded without hammering or otherwise applying forces which may causeinjury to the work structure.

Still another object of the present invention is to pro- Vide a novelanchor member or fastening device of the above described type which isconstructed so that it may repeatedly be applied to and removed from anapertured work structure without injury to the device or work structure.

Other objects and advantages of the present invention will becomeapparent from the following description and accompanying drawingswherein:

FIG. 1 is a perspective view showing a device incorporatingk features ofthe present invention and an end portion of a tool adapted to be used inassociation with the device;

FIG. 2 is a sectional view taken along line 2-2 in FIG. 1, and furthershows the device in an initial stage of assembly with an apertured workstructure;

FIG. 3 is similar to FIG. 2, but shows the device in an intermediatestage of assembly with a work structure;

FIG. 4 shows the device of FIGS. 1-3 fully assembled in a workstructure;

FIG. 5 is an exploded perspective view showing a fastening deviceincorporating a modified form of the present invention;

FIG. 6 is a sectional view showing the device of FIG. 5, partiallyassembled with an apertured work structure;

FIG. 7 is a sectional view showing the device of FIG. 5, fully assembledwith an apertured work structure;

FIG. 8 is a cross-sectional view taken along line 8-8 in FIG. 6;

FIG. 9 is a cross-sectional view taken along line 9-9 in FIG. 7;

FIG. 10 is a perspective view showing a further modified form of thepresent invention;

FIG. 11 is a sectional view showing the device of FIG. 10, partiallyassembled with a work structure;

FIG. 12 is an exploded perspective view, partially broken away, showinganother embodiment of the present invention;

FIG. 13 is a sectional view of the device of FIG. 12, partiallyassembled with a work structure;

FIG. 14 is a sectional view showing the device of FIGS. 12 and 13 fullyassembled with a work structure; and

FIGS. 15 and 16 respectively show different forms of an expansionelement usable in the device of FIGS. 12- 14.

Referring now more specifically to the drawings wherein like parts aredesignated by the same numerals throughout the various figures, a device20 incorporating features of the present invention is shown in FIGS.l-4. The device 20 in this embodiment is preferably molded from a toughdeformable and resilient plastic material such as nylon. While thedevice 26 may be modified so as to serve various functions, theembodiment shown is particularly adapted for fastening or anchoring achannel shaped molding strip 22 with respect to an apertured workstructure or panel 24.

The device 20 is provided with an axially extending shank portion 26adapted to extend through an aperture 28 in the work structure or thepanel 24. A laterally or radially extending head portion 30 isintegrally formed with a trailing end of the shank portion 26 foroverlying the outer surface of the work structure and for cooperativeengagement with the molding strip 22. In this embodiment the headportion 30 is provided with beveled margins 32 and 34 extending upwardlyand outwardly from the back or clamping face 36 of the head portion.These beveled margins are respectively adapted to overlie and retaininturned marginal flanges 38 and 40 of the molding strip 22. It is to beunderstood that the head portion 30 may be adapted for cooperation withvarious workpieces other than the molding strip 22; and, if desired, thedevice 26 with or without a modified head portion could be used forsecuring a plurality of apertured workpieces together or with respect tothe apertured panel or workpiece 24.

As shown best in FIGS. 2, 3 and 4, the shank portion 26 is hollow andcomprises a relatively thin and flexible peripheral and axiallyextending wall structure including opposite sides or the wall sections4244 and 4648. An end flange 50 is integrally formed with entering endextremities of the side walls 42-4-4 and 46-48.

As shown in FIGS. 12, the shank portion 26 is for-med so that it has atransverse cross-section which is substantially uniform in size andshape throughout the length of the shank portion. Furthermore, the outershape and dimensions of the shank portion 26 are similar to, butslightly smaller than the shape and dimensions of the aperture 28through the work structure 24, so that the shank portion may be readilyinserted into the aperture without any need for pounding or forcingwhich might cause injury to the work structure.

In accordance with a feature of the present invention the device 20 isprovided with means for expanding side Walls of shank portion behind thework structure or panel 24 as shown in FIG. 3 so as to provide shoulders55 and 56 cooperable with head portion 30 for securing the device withrespect to the workpiece or panel 24-. The expanding means in thisembodiment comprises an elongated pin or strut element 54 preferablyhaving a generally elliptical transverse cross-section. The pin element54 is initially molded integrally with the remainder of the device andis joined to the head portion 36 by a thin breakable connection 57. Thehead and shank portions 30 and 26 have a central opening 59 of uniformtransverse dimensions of substantially the same elliptical shape as thepin 54.

Upon application of the device to the workpiece, the pin is adapted tobe forced inwardly to break the connection 57 and permit shifting of thepin to the position shown in FIG. 3 in which thepin is located withinthe shank portion between opposite sides 42 and 44. In this position thepin extends from the end flange 50 toward and adjacent to the headportion 31 but sufiiciently short of the head portion so that the freeterminal end 58 of the pin or strut element 54 is located entirelythrough and beyond the work structure or panel 24 when the device isfully applied to the work structure. The elliptical configuration of thestrut element makes it relatively thin in one direction while having asubstantial width between longitudinal edges 60 and 62 thereof, whichwidth is materially greater than the distance between inner surfaces ofthe opposite sidewalls 42 and 44. The resilient deformable material ofthe shank 26 enables the pin to be twisted about its longitudinal axisfrom its normal position shown in FIGS. 2 and 3, to a position disposedtransversely of the wall sections 42 and 44 as shown in FIG. 4. Thus,the side walls 42 and 44 may be readily expanded without pounding andwithout applying axially directed forces to the device 20 which mightdent or otherwise injure the workpiece 24, particularly if the workpiece24 is a relatively thin panel, by twisting the element 54 so that itbecomes wedged between the side walls 42 and 44 as shown in FIG. 3.

In order to secure device 20 with respect to the work structure, ascrewdriver-like tool 76 is preferably provided, a portion which isshown in FIG. 1, which tool includes an elongated shank adapted to beinserted into a slot 61 in the pin 54 and through the portion of thepart of opening 59 in the head portion 30. With the aid of this tool,the strut element may quickly and easily be forced into the shank 26 andtwisted from its normal position shown in FIGS. 2 and 3 to the positionshown in FIG. 4. During this twisting movement, the opposite side walls42 and 44 will expand sufiiciently to provide the shoulders 55 and 56,and provide a resilient gripping of the pin element so that the pinelement will be positively locked in the twisted condition, and thedevice 20 will be positively secured with respect to the work structureor panel. However, it is further to be noted that the device may beremoved from the work structure, if desired, and without injury theretosimply by utilizing the tool 76 for applying a twisting force to the pinelement, which is sufficient to cause the pin element to return to itsoriginal position. After the pin element has been disengaged in thismanner, the resiliency of the plastic will cause the opposite side walls42 and 44 to return substantially to their original or normal condition,so that the device may be readily withdrawn from the work structureaperture.

As indicated above, the shank portion in its normal conditionsubstantially fills the aperture 28 in the work structure or panel. Whenthe shank is expanded, the side walls thereof are urged into sealingengagement with the edges of the work structure aperture and the workstructure aperture is effectively sealed. The slot 61 terminates shortof the inner end of the element 54, so that the element 54 will providean effective plug for sealing the aperture through the shank portion.

FIGS. 5-9 show another embodiment of the present invention which is'similar to the structure shown in FIGS. 1-4 as indicated :by theapplication of identical reference numerals with the suffix b added tocorresponding elements. This embodiment differs primarily in that thecomplementary cross-sectional configurations of the strut or expandingelement 54b and the aperture 59b are varied from the above disclosedelliptical shape. In this embodiment the strut element 54b is providedwith a plurality of eccentric cam portions 86 spaced around theperiphery thereof and the wall of the aperture 59b is formed withcomplementary cam surfaces 88. As shown best in FIG. 9, the cam portions86 are adapted to mate with the cam surfaces 88 when the element 547? isin a first position so that the element may be readily inserted,

into the aperture 5%. However, upon rotation of the element 54b, towardthe position shown in FIG. 9, the high points of the camportions 86 areprogressively forced into lower portions of the cam surfaces 88 so as toexpand the shank behind the work structure.

The strut or expanding element 54b is further provided with means forresisting retrograde rotation. This means comprises ratchet teeth 90which are peripherally spaced and which are adapted to engage the wallof the aperture 59b in a manner which permits expanding rotation of theelement 54b, but resists return rotation. While the element 54b is shownseparate from the head and shank portions of the device, it is to beunderstood that it may initially be integrally joined thereto in themanner contemplated by the embodiment shown in FIGS. 1-4. It is furtherto be understood that the ratchet teeth 90 or similar means may beformed on the expanding or strut element of the embodiment shown inFIGS. 1-4 for positively locking such element in the shank expandingposition and the pin or strut element of FIGS. 1-4

7 may be formed separately from the head 30, if desired.

FIGS. 10 and 11 show still another embodiment which is similar to thedevices described above and particularly the structure of FIGS. 5-9 asindicated by the application of identical reference numerals with thesuffix c substituted for the suffix b to corresponding elements. Thisembodiment shows a slightly modified cam structure for expanding theshank portion of the device. Furthermore this embodiment contemplatesthe provision of axially facing cam surfaces 92 and axially extendingabutment surfaces 94 cooperable with a complementary tool, not shown,which may be used for rotating the element 54c within the shank portion.

A further embodiment of the present invention is shown in FIGS. 12-14 inwhich elements corresponding to those described above are indicated bythe application of iden tical reference numerals with the suflix d addedor substituted for the previous sufixes. In this embodiment, theexpanding element 54d is a thin flexible wafer-like element which iselongated so that it has a length along a major axis greater than theinternal diameter of the shank portion 26d and a dimension along a minoraxis less than the internal diameter of the shank. Thus the element 54dmay be readily inserted lengthwise into the shank portion.

The shank portion 26d and the element 54d are provided with cooperablemeans for facilitating turning of the element 54d about its minor axisand about an axis extending transversely of the shank portion 26d so asto expand the shank portion as shown in FIG. 14. In the embodimentshown, the cooperable means include oppositely projecting pin or pivotelements 96 and 98 on the element 54d and aligned with the minor axisthereof. In addition, socket elements 100 and 102 are integrally formedwith inner surfaces of the shank portion 26d and are oppositely disposedfor receiving the pivot pins 96 and 98 respectively. As shown in thedrawings, the socket elements 1% and 102 have a generally U-shapedconfigration so that the pin elements 96 and 98 may be slipped intoassociation therewith when the element 54d is inserted into the shankportion 26d as shown in FIG. 13. It will be appreciated that the element54d may be turned to the position shown in FIG. 14 by pushing on the 1outwardly projecting end portion thereof with the aid of any suitableelongated tool so 'as to cause the element to pivot around the commonaxis of the pins 96 and 98.

FIGS. 15 and 16 respectively show elements 54:; and 54] which may besubstituted for the element 54d described above. These elements arerespectively provided with central apertures 104a and 104 foraccommodating elongated pins, rods, shanks, or fastener elements such asscrews and the like. The aperture 104s is defined by a plurality ofaxially inclined resilient prongs 106a which are specially adapted toengage and retain a pin or the like having a smooth surface while theaperture 104 is defined by a helically deflected inner marginal portion106) so that the element 541 is especially suitable for accommodating ascrew member or the like.

While the preferred embodiments of the present invention have been shownand described herein, it is obvious that many structural details may bechanged without departing from the spirit and scope of the appendedclaims.

What is claimed is:

1. A fastening device comprising a resiliently transversely expandableplastic shank portion insertable through an aperture in a workstructure, a head portion integrally joined to a trailing end of shankportion and projecting laterally from the shank portion for overlyingone side of the work structure, said shank and head portions having anaxially extending opening therein, said shank and head portions havinginternal cross sectional configurations of substantially the same sizeand shape, said internal cross sectional configuration having a firstpredetermined transverse dimension and a second transverse dimensiongreater than said first dimension, said shank and head portions joiningeach other at a circumferentially continuous junction, said shankportion having circumferentially continuous walls extending axially fromsaid junction, said shank portion having an exterior transverse crosssection having its maximum dimensions adjacent said junction and similarto and not substantially greater than corresponding dimensions of theaperture in the work structure for facilitating easy insertion of theshank portion through the aperture, and substantially filling theaperture, and a rotatable expansion element pivotally locatable in saidopening and having transverse dimensions generally corresponding to saidinternal transverse dimensions of said shank portion and having one ofsaid transverse dimensions in one direction greater than said firstpredetermined transverse dimension of said opening and a secondtransverse dimension less than said first predetermined transversedimension of said opening for enabling the expansion element to berotated within said opening for expanding the shank portion behind awork structure during assembly of the device with the work structure,said expansion element being located substantially entirely within saidshank portion and avoiding axially directed engagement with said headportion when said device is fully assembled with the work structure.

2. A fastening device, as defined in claim 1, wherein said transversecross-sections are substantially elliptical.

3. A fastening device, as defined in claim 1, wherein said expansionelement and said shank portion include cooperable eccentric cam surfacemeans.

4. A fastening device, as defined in claim 1, which includes tooth meansprojecting between said element and shank portion for resistingretrograde rotation of the element after said element has been turned soas to expand the shank portion.

5. A fastening device, as defined in claim 1, wherein said expansionelement is disposed for rotation about a central longitudinal axis ofsaid shank portion.

6. A fastening device, as defined in claim 1, wherein said expansionelement is disposed for rotating about a transverse axis of said shankportion.

7. A fastening device as defined in claim 6, wherein said expansionelement includes central aperture means for accommodating and retainingan elongated element inserted axially into said shank portion when saidexpansion element is turned for expanding said shank portion.

References Cited by the Examiner UNITED STATES PATENTS 2,733,067 1/1956Moore et al 242 14 X FOREIGN PATENTS 1,115,678 1/1956 France.

WILLIAM FELDMAN, Primary Examiner. E. SIMONSEN, Assistant Examiner.

1. A FASTENING DEVICE COMPRISING A RESILIENTLY TRANSVERSELY EXPANDABLEPLASTIC SHANK PORTION INSERTABLE THROUGH AN APERTURE IN A WORKSTRUCTURE, A HEAD PORTION INTEGRALLY JOINED TO A TRAILING END OF SHANKPORTION AND PROJECTING LATERALLY FROM THE SHANK PORTION FOR OVERLYINGONE SIDE OF THE WORK STRUCTURE, SAID SHANK AND HEAD PORTIONS HAVING ANAXIALLY EXTENDING OPENING THEREIN, SAID SHANK AND HEAD PORTIONS HAVINGINTERNAL CROSS SECTIONAL CONFIGURATIONS OF SUBSTANTIALLY THE SAME SIZEAND SHAPE, SAID INTERNAL CROSS SECTIONAL CONFIGURATION HAVING A FIRSTPREDETERMINED TRANSVERSE DIMENSION AND A SECOND TRANSVERSE DIMENSIONGREATER THAN SAID FIRST DIMENSION, SAID SHANK AND HEAD PORTIONS JOININGEACH OTHER AT A CIRCUMFERENTIALLY CONTINUOUS JUNCTION, SAID SHANKPORTION HAVING CIRCUMFERENTIALLY CONTINUOUS WALLS EXTENDING AXIALLY FROMSAID JUNCTION, SAID SHANK PORTION HAVING AN EXTERIOR TRANSVERSE CROSSSECTION HAVING ITS MAXIMUM DIMENSIONS ADJACENT SAID JUNCTION AND SIMILARTO AND NOT SUBSTANTIALLY GREATER THAN CORRESPONDING DIMENSIONS OF THEAPERTURE IN THE WORK STRUCTURE FOR FACILITATING EASY INSERTION OF THE